In recent years, electric vehicles and hybrid vehicles are attracting attention as environment-friendly vehicles. An electric vehicle has a vehicle-mounted battery charged from an external source. Furthermore, research efforts are now being made to allow a vehicle-mounted battery to be charged from an external source in some hybrid vehicles.
When a vehicle-mounted battery is to be charged from an external source, the time required for charging becomes an issue. Charging must be carried out with high-amperage current to reduce the time required for charging.
Japanese Patent Laying-Open No. 2002-233070 (PTL 1) discloses a battery charging device that allows charging in a short time even if the temperature of the battery is increased during rapid charging.